Thin film deposition method and thin film deposition apparatus
By infiltrating a metal into resist films and forming a protective film using silanol-containing precursors, the method enhances etching resistance, preventing tearing and maintaining pattern integrity during etching processes.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOKYO ELECTRON LTD
- Filing Date
- 2022-09-27
- Publication Date
- 2026-05-11
AI Technical Summary
Existing film forming methods do not adequately enhance the etching resistance of resist films, leading to potential tearing during etching processes, especially when the resist films are thin.
A method involving the infiltration of a metal-containing gas into the resist film followed by the application of a silanol-containing precursor gas to form a protective film selectively on the upper surface, enhancing etching resistance by limiting metal infiltration to the upper surface and preventing etching damage.
The method significantly improves the etching resistance of resist films, maintaining pattern integrity during etching by preventing tearing and ensuring consistent line widths in the resulting patterns.
Smart Images
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Abstract
Description
Technical Field
[0001] The present disclosure relates to a film forming method and a film forming apparatus.
Background Art
[0002] Patent Document 1 discloses a technique of infiltrating a metal into a resist film. Patent Document 2 discloses a technique of forming a thin film of silicon dioxide on a substrate by alternately supplying a metal precursor such as trimethylaluminum (TMA) and a silanol such as tris(tert-pentoxy)silanol (TPSOL) to the substrate.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Patent Document 2
Summary of the Invention
Problems to be Solved by the Invention
[0004] One aspect of the present disclosure provides a technique for improving the etching resistance of a resist film.
Means for Solving the Problems
[0005] A film forming method according to one aspect of the present disclosure includes preparing a substrate having a resist film with an opening formed on an upper surface thereof, supplying a metal-containing gas containing a metal to the substrate to infiltrate the metal into at least an upper portion of the resist film, and supplying a precursor gas containing a silanol to the substrate to selectively form a protective film containing silicon and oxygen on the upper surface of the resist film compared to side surfaces and a bottom surface of the opening. The aforementioned metal is a metal or metalloid having Lewis acid properties, or a compound thereof.
Effects of the Invention
[0006] According to one aspect of this disclosure, the etching resistance of the resist film can be improved. [Brief explanation of the drawing]
[0007] [Figure 1] Figure 1 is a flowchart showing a film deposition method according to one embodiment. [Figure 2] Figure 2(A) shows an example of S101, Figure 2(B) shows an example of S102, and Figure 2(C) shows an example of S103. [Figure 3] Figure 3(A) shows a modified version of Figure 2(A), Figure 3(B) shows a modified version of Figure 2(B), and Figure 3(C) shows a modified version of Figure 2(C). [Figure 4] Figure 4 shows an example of the infrared spectral spectrum of a resist film supplied with TMA gas only, and an example of the infrared spectral spectrum of a resist film supplied with TMA gas and TPSOL gas in that order. [Figure 5] Figure 5 is a flowchart showing the post-processing steps of a film deposition method according to one embodiment. [Figure 6] Figure 6(A) shows an example of S201, Figure 6(B) shows an example of S202, and Figure 6(C) shows an example of S203. [Figure 7] Figure 7 is a flowchart showing the film formation method according to the first modified example. [Figure 8] Figure 8(A) shows an example of S301, Figure 8(B) shows an example of S302, Figure 8(C) shows an example of S303, Figure 8(D) shows an example of S304, Figure 8(E) shows an example of S305, and Figure 8(F) shows an example of S306. [Figure 9] Figure 9 is a flowchart showing the film formation method according to the second modified example. [Figure 10]Figure 10(A) shows an example of S401, Figure 10(B) shows an example of S402, Figure 10(C) shows an example of S403, Figure 10(D) shows an example of S404, Figure 10(E) shows an example of S405, and Figure 10(F) shows an example of S406. [Figure 11] Figure 11 is a cross-sectional view showing a film deposition apparatus according to one embodiment. [Modes for carrying out the invention]
[0008] Embodiments of this disclosure will be described below with reference to the drawings. In each drawing, the same or corresponding components are denoted by the same reference numerals, and their descriptions may be omitted.
[0009] A film deposition method according to one embodiment will be described with reference to Figures 1 to 3. The film deposition method includes, for example, steps S101 to S103 shown in Figure 1. Step S101 includes preparing the substrate 100 shown in Figure 2(A). Preparing the substrate 100 includes, for example, loading the substrate 100 into the processing container.
[0010] The substrate 100 includes, for example, a base substrate 110, an etching target film 120, a hard mask film 130, and a resist film 140, in this order. The base substrate 110 is, for example, a silicon wafer, a compound semiconductor wafer, or a glass substrate.
[0011] The film to be etched 120 is a film that transfers the aperture pattern of the resist film 140. The film to be etched 120 is, for example, a spin-on carbon film. A spin-on carbon film is an amorphous film that mainly contains carbon (C).
[0012] The hard mask film 130 is used when the film thickness of the resist film 140 is thin. As an example of a resist film 140 with a thin film thickness, a resist film for EUV (Extreme Ultraviolet) exposure can be mentioned. The hard mask film 130 is, for example, a spin-on glass film. The spin-on glass film is an amorphous film mainly containing silicon (Si) and oxygen (O).
[0013] An opening is formed on the upper surface of the resist film 140. The resist film 140 is formed of a photoresist composition. The photoresist composition is, for example, a chemically amplified type. The resist film 140 has a functional group that incorporates a metal in step S102 described later. The functional group may be a common one, for example, a phenyl group or an acrylic group.
[0014] As shown in FIG. 2(B), step S102 includes supplying a metal-containing gas containing a metal to the substrate 100 to infiltrate the metal into at least the upper part of the resist film 140, that is, to make the metal penetrate into at least the upper part of the resist film 140. In FIG. 2(B), 140A is the part of the resist film 140 where the metal has infiltrated.
[0015] The metal penetrates from the surface to the inside of the resist film 140, for example, by a nucleophilic substitution reaction. The metal includes a metal or a metalloid having Lewis acid characteristics, or a compound thereof. Specifically, the metal includes, for example, one or more elements selected from Al, Ti, Zr, Zn, Hf, B, and In.
[0016] As the metal-containing gas, for example, an organometallic compound gas is used. The smaller the molecular weight of the organometallic compound gas, the easier it is for the metal to infiltrate. The organoaluminum compound gas is, for example, trimethylaluminum (TMA: Trimethylaluminium) gas or triethylaluminum (TEA: Triethylaluminium) gas. The organotitanium compound gas is, for example, tetrakis(dimethylamino)titanium (TDMAT: Tetrakis(dimethylamino)titanium) gas.
[0017] Step S102 includes, for example, supplying a metal-containing gas (step S102a) and supplying a purge gas (step S102b). The purge gas discharges the metal-containing gas remaining inside the processing vessel to the outside of the processing vessel. Also, the purge gas discharges the excess metal-containing gas physically adsorbed on the surface of the resist film 140 to the outside of the processing vessel.
[0018] Step S102 may include checking whether steps S102a and S102b have been performed N (N is an integer of 1 or more) times (step S102c). When N is an integer of 2 or more, step S102 performs steps S102a and S102b a plurality of times. However, N may be 1.
[0019] In the nth (n is an integer of 1 or more) step S102b, the purge gas discharges the excess metal-containing gas physically adsorbed on the surface of the resist film 140 to the outside of the processing vessel. As a result, in the (n + 1)th step S102a, the metal easily infiltrates from the surface into the resist film 140.
[0020] The infiltration depth and amount of the metal are mainly controlled by the number of times N of performing steps S102a and S102b, the pressure of the metal-containing gas, and the temperature of the substrate 100. The larger the number of times N of performance, the larger the pressure of the metal-containing gas, and the higher the temperature of the substrate 100, the easier the metal infiltrates into the resist film 140.
[0021] By adjusting the pressure of the metal-containing gas or the temperature of the substrate 100, as shown in FIG. 2(B), it is also possible to infiltrate the metal only above the resist film 140. Note that, as shown in FIG. 3(A), the resist film 140 may have a multilayer structure so that the metal selectively infiltrates above the resist film 140.
[0022] As shown in Figure 3(A), the resist film 140 has an uppermost layer 141 and one or more (one in Figure 3(A)) lower layers 142 provided below the uppermost layer 141. The uppermost layer 141 is more permeable to metal than all of the lower layers 142. As a result, as shown in Figure 3(B), metal can be selectively permeated into the upper part of the resist film 140.
[0023] The uppermost layer 141 has a higher surface density of metal-incorporating functional groups compared to all the lower layers 142. The surface density of functional groups can be measured, for example, by X-ray photoelectron spectroscopy (XPS). The region in which metal infiltration occurs can be controlled by the surface density of functional groups.
[0024] Step S102 is preferably performed at a temperature of 200°C or lower to suppress ashing of the resist film 140, and it is also preferable not to use plasma. An example of the processing conditions for steps S102a and S102b is shown below. <Step S102a> Substrate temperature: 20℃~250℃ TMA gas flow rate: 10 sccm to 1,000 sccm TMA gas supply time: 10 seconds to 300 seconds Internal pressure of the processing container: 10 Pa ~ 10,000 Pa <Step S102b> Substrate temperature: 20℃~250℃ N2 gas flow rate: 10 sccm to 10,000 sccm N2 gas supply time: 10 seconds to 300 seconds Internal pressure of the processing container: 10 Pa to 10,000 Pa.
[0025] Step S103 includes supplying a silanol-containing precursor gas to the substrate 100, as shown in Figure 2(C) or Figure 3(C), to form a protective film 150 selectively containing silicon (Si) and oxygen (O) on the upper surface of the resist film 140 compared to the side and bottom surfaces of the openings of the resist film 140. The metal impregnated into the resist film 140 functions as a catalyst to promote the reaction that forms the protective film 150.
[0026] The protective film 150 grows starting from the metal that has infiltrated the resist film 140. By limiting the area to which the metal infiltrates, the protective film 150 can be selectively formed, and the width of the opening in the resist film 140 can be maintained. The protective film 150 is hardly formed on the sides and bottom of the opening in the resist film 140. The bottom of the opening in the resist film 140 is the surface of the hard mask film 130.
[0027] Examples of precursor gases used include tris(tert-pentoxy)silanol (TPSOL), triethylsilanol, methylbis(tert-pentoxy)silanol, or tris(tert-butoxy)silanol (TBSOL).
[0028] Step S103 includes, for example, the supply of a precursor gas (step S103a) and the supply of a purge gas (step S103b). The purge gas discharges the precursor gas remaining inside the processing container to the outside of the processing container. The purge gas also discharges any excess precursor gas physically adsorbed on the surface of the resist film 140 to the outside of the processing container.
[0029] Step S103 involves performing steps S103a and S103b only once, but steps S103a and S103b may be performed multiple times, similar to step S102. In the nth (where n is an integer greater than or equal to 1)th step S103b, the purge gas discharges excess precursor gas physically adsorbed on the surface of the resist film 140 to the outside of the processing container. This facilitates the growth of the protective film 150 in the (n+1)th step S103a.
[0030] Step S103 is preferably performed at a temperature of 200°C or lower in order to suppress ashing of the resist film 140, and it is also preferable not to use plasma. An example of the processing conditions for steps S103a and S103b is shown below. <Step S103a> Substrate temperature: 20℃~250℃ TPSOL gas flow rate: 10 sccm to 1,000 sccm TPSOL gas supply time: 10 seconds to 900 seconds Internal pressure of the processing container: 10 Pa ~ 10,000 Pa <Step S103b> Substrate temperature: 20℃~250℃ N2 gas flow rate: 10 sccm to 10,000 sccm N2 gas supply time: 10 seconds to 300 seconds Internal pressure of the processing container: 10 Pa to 10,000 Pa.
[0031] In Figure 4, the dashed line shows an example of the infrared spectral spectrum of the resist film 140 supplied with TMA gas only, and the solid line shows an example of the infrared spectral spectrum of the resist film 140 supplied with TMA gas and TPSOL gas in that order. Comparing the solid and dashed lines, it can be seen that a silicon oxide film can be formed on the surface of the resist film 140 by supplying TMA gas and TPSOL gas in that order.
[0032] Referring to Figures 5 and 6, the post-processing steps of a film deposition method according to one embodiment will be described. The post-processing steps include, for example, steps S201 to S203 shown in Figure 5. Step S201 includes etching the hard mask film 130 using the resist film 140 protected by the protective film 150, as shown in Figure 6(A).
[0033] The protective film 150 protects the upper surface of the resist film 140, thereby preventing the resist film 140 from tearing even if its thickness is uneven. This is particularly effective when the resist film 140 is thin. An example of a thin resist film 140 is a resist film used for EUV (Extreme Ultraviolet) exposure.
[0034] The protective film 150 is hardly formed on the sides and bottom of the openings in the resist film 140, and is mainly formed on the top surface of the resist film 140. Therefore, an opening pattern with the same line width as the resist film 140 can be formed on the hard mask film 130. Note that the hard mask film 130 is optional, and step S201 is optional.
[0035] Step S202 includes etching the film to be etched 120 using the resist film 140 protected by the protective film 150, as shown in Figure 6(B). The protective film 150 protects the upper surface of the resist film 140, which prevents the resist film 140 from tearing even if the thickness of the resist film 140 is uneven.
[0036] As previously described, the protective film 150 is hardly formed on the sides and bottom of the openings in the resist film 140, and is mainly formed on the top surface of the resist film 140. Therefore, an opening pattern with the same line width as the resist film 140 can be formed on the film to be etched 120.
[0037] Step S203 includes peeling off the hard mask film 130, the resist film 140, and the protective film 150, as shown in Figure 6(C). For example, step S203 includes removing the resist film 140 and the protective film 150 by etching the hard mask film 130 with dilute hydrofluoric acid (DHF).
[0038] Referring to Figures 7 and 8, a film deposition method according to the first modified example will be described. The film deposition method includes, for example, steps S301 to S306 shown in Figure 7. Step S301 includes preparing the substrate 100 shown in Figure 8(A). Preparing the substrate 100 includes, for example, bringing the substrate 100 into the processing container.
[0039] Step S302 includes supplying a metal-containing gas to the substrate 100, as shown in Figure 8(B), to impregnate at least the upper part (the entire part in Figure 8(B)) of the resist film 140 with metal. In Figure 8(B), 140A is the portion of the resist film 140 that has been impregnated with metal.
[0040] Step S303 includes forming a planarization film 160 on the resist film 140 to flatten the steps in the resist film 140, as shown in Figure 8(C). The planarization film 160 fills the openings in the resist film 140. The planarization film 160 may be an organic film, similar to the resist film 140. However, unlike the resist film 140, the planarization film 160 is not impregnated with metal.
[0041] Step S304 involves exposing the upper part of the resist film 140 by etching or other methods to remove the planarization film 160, as shown in Figure 8(D). The planarization film 160 fills the openings in the resist film 140, and the sides of these openings are covered by the planarization film 160. In Figure 8(D), the upper surface of the planarization film 160 and the upper surface of the resist film 140 are arranged on the same plane, but this is not limited to this. It is sufficient that the sides of the openings are covered by the planarization film 160; for example, the central part of the planarization film 160 may be concave.
[0042] Step S305 includes forming a protective film 150 on top of the resist film 140, as shown in Figure 8(E). The protective film 150 grows starting from the metal that has infiltrated the resist film 140. The planarization film 160, unlike the resist film 140, is not infiltrated with metal. Therefore, the protective film 150 is selectively formed on top of the resist film 140 compared to the top of the planarization film 160. Step S305 is carried out in the same manner as step S103 in Figure 1.
[0043] Step S306 includes removing the planarization film 160 that blocks the openings in the resist film 140 by etching or the like, as shown in Figure 8(F). As a result, the layer beneath the planarization film 160, such as the hard mask film 130, is exposed at the openings in the resist film 140. If the planarization film 160 is an organic film, the difference in etching rates between the planarization film 160 and the protective film 150 is large, and the thickness of the protective film 150 hardly decreases.
[0044] After step S306, the substrate 100 is subjected to the post-processing shown in Figure 5. The post-processing is the same as in the above embodiment, so its description is omitted.
[0045] Referring to Figures 9 to 10, a film deposition method according to a second modified example will be described. The film deposition method includes, for example, steps S401 to S406 shown in Figure 9. Step S401 includes preparing the substrate 100 shown in Figure 10(A). Preparing the substrate 100 includes, for example, loading the substrate 100 into the processing container.
[0046] Step S402 includes supplying a metal-containing gas to the substrate 100, as shown in Figure 10(B), to impregnate at least the upper part (the entire part in Figure 10(B)) of the resist film 140 with metal. In Figure 10(B), 140A is the portion of the resist film 140 that has been impregnated with metal.
[0047] Step S403 includes forming a conformal film 170 along the step of the resist film 140 on the upper surface of the resist film 140 and on the side surface of the opening of the resist film 140, as shown in Figure 10(C). The conformal film 170 is not formed on the bottom surface of the opening of the resist film 140, but may be formed there. The conformal film 170 is, for example, an inorganic film.
[0048] The conformal film 170 may be formed in the same manner as the protective film 150. That is, the conformal film 170 may be formed using a precursor gas containing silanol. In this case, the conformal film 170 is formed on the top surface and the sides of the opening of the resist film 140, and hardly at all on the bottom surface of the opening.
[0049] Step S404 involves selectively etching the upper part of the conformal film 170 using anisotropic etching or the like, as shown in Figure 10(D), thereby exposing the upper part of the resist film 140. After step S404, the sides of the openings in the resist film 140 remain covered by the conformal film 170.
[0050] If the conformal film 170 is formed on the bottom surface of the opening in the resist film 140 in step S403, step S404 may also include removing the conformal film 170 formed on the bottom surface of the opening in the resist film 140.
[0051] Step S405 includes forming a protective film 150 on top of the resist film 140, as shown in Figure 10(E). The protective film 150 grows starting from the metal that has infiltrated the resist film 140. The conformal film 170, unlike the resist film 140, is not infiltrated with metal. Therefore, the protective film 150 is selectively formed on top of the resist film 140. Step S405 is carried out in the same manner as step S103 in Figure 1.
[0052] Step S406 includes removing the conformal film 170 remaining on the sides of the openings in the resist film 140 by etching or the like, as shown in Figure 10(F). At this time, the conformal film 170 and the protective film 150 may be etched simultaneously. If the thickness of the conformal film 170 is thinner than the thickness of the protective film 150, the protective film 150 can be left on top of the resist film 140.
[0053] After step S406, the substrate 100 is subjected to the post-processing shown in Figure 5. The post-processing is the same as in the above embodiment, so its description is omitted.
[0054] Next, with reference to Figure 11, a film deposition apparatus 101 that carries out at least a part of the film deposition method shown in Figure 1, Figure 7, or Figure 9 will be described. Note that the film deposition apparatus 101 shown in Figure 11 is an example of a batch type that processes multiple substrates 100 arranged vertically simultaneously, but a single-wafer type that processes substrates 100 one at a time may also be used. The batch type film deposition apparatus will be described below.
[0055] The film deposition apparatus 101 includes a processing container 1. The processing container 1 has a cylindrical inner tube 1A with a roof that is open at the bottom, and a cylindrical outer tube 1B with a roof that is open at the bottom and covers the outside of the inner tube 1A. The inner tube 1A and the outer tube 1B are made of a heat-resistant material such as quartz and are arranged coaxially to form a double-tube structure. A cylindrical metal manifold 3 is connected to the opening at the bottom of the processing container 1 via a sealing member 4 such as an O-ring.
[0056] The manifold 3 supports the lower end of the processing container 1, and a wafer boat 5, on which substrates 100 are arranged in multiple layers, is inserted into the processing container 1 from below the manifold 3. In this way, a large number of substrates 100 are housed in the processing container 1 in a substantially horizontal manner with spacing along the vertical direction. The wafer boat 5 is made of, for example, quartz. The wafer boat 5 has three rods 6 (two are shown in Figure 11), and the large number of substrates 100 are supported by grooves (not shown) formed in the rods 6. The wafer boat 5 is an example of a substrate holding part.
[0057] The wafer boat 5 is placed on the table 8 via a heat-insulating tube 7 made of quartz. The table 8 is supported on a rotating shaft 10 that passes through a metal (stainless steel) cover 9 that opens and closes the opening at the lower end of the manifold 3.
[0058] A magnetic fluid seal 11 is provided at the penetration portion of the rotating shaft 10, which hermetically seals the rotating shaft 10 and supports it so that it can rotate. A sealing member 12 is provided between the periphery of the lid 9 and the lower end of the manifold 3 to maintain airtightness inside the processing container 1.
[0059] The rotating shaft 10 is attached to the tip of an arm 13 supported by a lifting mechanism (not shown), such as a boat elevator, and the wafer boat 5 and the lid 9 move up and down together and are inserted into and removed from the processing container 1. Alternatively, a table 8 may be fixed to the lid 9 side so that the substrate 100 can be processed without rotating the wafer boat 5.
[0060] The film deposition apparatus 101 includes a gas supply unit 20. The gas supply unit 20 supplies gas into the processing container 1 (specifically, the inner tube 1A). The gas supply unit 20 has gas supply pipes 21, 22, and 23. The gas supply pipes 21 and 22 are made of, for example, quartz, and penetrate the side wall of the manifold 3 inward, bent upward, and extend vertically. Multiple gas holes 21g and 22g are formed at predetermined intervals in the vertical portions of the gas supply pipes 21 and 22 over a length corresponding to the wafer support range of the wafer boat 5. Each gas hole 21g and 22g discharges gas horizontally. The gas supply pipe 23 is made of, for example, quartz, and consists of a short quartz tube that penetrates the side wall of the manifold 3. The gas supply pipe 23 may also penetrate the side wall of the manifold 3 inward, bent upward, and extend vertically, similar to the gas supply pipes 21 and 22.
[0061] The gas supply pipe 21 has a vertical portion (the vertical portion where the gas holes 21g are formed) located inside the processing container 1 (for example, the inner pipe 1A). A metal-containing gas is supplied to the gas supply pipe 21 from a gas supply source 21a via a gas pipe. The metal-containing gas is, for example, TMA gas. A flow controller 21b and an on-off valve 21c are provided in the gas pipe. As a result, the metal-containing gas from the gas supply source 21a is supplied to the inside of the processing container 1 (for example, the inner pipe 1A) via the gas pipe and the gas supply pipe 21. The metal-containing gas contains a metal that is impregnated into the resist film 140.
[0062] The gas supply pipe 22 has its vertical portion (the vertical portion where the gas holes 22g are formed) located inside the processing container 1 (for example, the inner pipe 1A). A precursor gas is supplied to the gas supply pipe 22 from a gas supply source 22a via gas piping. The precursor gas is, for example, TPSOL gas. A flow controller 22b and an on / off valve 22c are provided in the gas piping. As a result, the precursor gas from the gas supply source 22a is supplied to the inside of the processing container 1 (for example, the inner pipe 1A) via the gas piping and the gas supply pipe 22. The precursor gas forms a protective film 150 containing silicon (Si) and oxygen (O) using a metal impregnated into the resist film 140 as a catalyst.
[0063] A purge gas is supplied to the gas supply pipe 23 from the gas supply source 23a via the gas piping. The purge gas is, for example, nitrogen (N2) gas, but it may also be argon (Ar) gas. A flow controller 23b and an on-off valve 23c are provided in the gas piping. As a result, the purge gas from the purge gas supply source is supplied to the inside of the processing container 1 (for example, the inner pipe 1A) via the gas piping and the gas supply pipe 23.
[0064] The film deposition apparatus 101 includes a gas discharge section 45 for discharging gas from inside the processing container 1. The gas discharge section 45 has an exhaust pipe 42 connected to the exhaust port 40 of the processing container 1. The exhaust port 40 is formed in the side wall of the manifold 3 and communicates with the exhaust port 41 of the inner tube 1A via a passage between the outer tube 1B and the inner tube 1A. The exhaust port 41 of the inner tube 1A is formed to be elongated vertically to correspond to the wafer boat 5. The exhaust pipe 42 is equipped with a pressure control valve 43 for controlling the pressure inside the processing container 1 and a vacuum pump 44.
[0065] The film deposition apparatus 101 is equipped with a heating mechanism 50. The heating mechanism 50 heats the processing container 1 and the substrate 100 inside it. The heating mechanism 50 is provided in a cylindrical shape so as to surround the outer circumference of the processing container 1.
[0066] The film deposition apparatus 101 includes a transport unit (not shown). The transport unit is a general-purpose transport robot. The transport unit loads and unloads the substrate 100 into and out of the processing container 1. The transport unit transports the substrate 100 while it is placed on the wafer boat 5.
[0067] The film deposition apparatus 101 includes a control unit 60. The control unit 60 is, for example, a computer and has an arithmetic unit such as a CPU (Central Processing Unit) and a storage unit such as memory. The storage unit stores programs that control various processes performed in the film deposition apparatus 101. The control unit 60 controls the operation of the film deposition apparatus 101 by causing the arithmetic unit to execute the programs stored in the storage unit.
[0068] The film deposition apparatus 101 only needs to perform at least a part of the film deposition method shown in Figure 1, Figure 7, or Figure 9. The film deposition apparatus 101 can perform all of steps S101 to S103 in Figure 1. The film deposition apparatus 101 can perform all of steps S301 to S306 in Figure 7. If step S303 is performed using a spin coater or the like, steps S301 to S302 and S304 to S306 can be performed excluding step S303. The film deposition apparatus 101 can perform steps S401 to S403 and S405 to S406 of steps S401 to S406 in Figure 9, excluding step S404. However, if the film deposition apparatus 101 has a configuration that allows for both isotropic etching and anisotropic etching (for example, a single-wafer apparatus), then all of steps S401 to S406 can be performed.
[0069] Furthermore, steps S102 to S103 shown in Figure 1 may be carried out inside the same processing container 1 or inside separate processing containers 1. Similarly, steps S302 to S306 shown in Figure 7 may be carried out inside the same processing container 1 or inside separate processing containers 1. Also, steps S402 to S406 shown in Figure 9 may be carried out inside the same processing container 1 or inside separate processing containers 1.
[0070] While embodiments of the film deposition method and film deposition apparatus relating to this disclosure have been described above, this disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These, too, naturally fall within the technical scope of this disclosure. [Explanation of Symbols]
[0071] 100 circuit boards 110 Substrate 120 Etching target film 130 Hard mask film 140 Resist film 150 Protective film
Claims
1. Prepare a substrate having a resist film with an opening formed on its upper surface, By supplying a metal-containing gas to the substrate, the metal is impregnated into at least the upper part of the resist film. By supplying a precursor gas containing silanol to the substrate, a protective film containing silicon and oxygen is selectively formed on the upper surface of the resist film compared to the side and bottom surfaces of the opening. It has, The aforementioned metal is a metal or metalloid having Lewis acid properties, or a compound thereof, and is used in a film formation method.
2. The resist film comprises an uppermost layer and one or more lower layers provided below the uppermost layer. The film-forming method according to claim 1, wherein the uppermost layer is more easily permeated with the metal than all of the lower layers.
3. The method for forming a film according to claim 2, wherein the uppermost layer has a higher surface density of metal-incorporating functional groups compared to all of the lower layers.
4. A method for forming a film according to claim 1, comprising, in this order: impregnating the resist film with the metal at least into the upper part of the resist film; forming a planarizing film on the resist film to flatten any steps in the resist film; exposing the upper part of the resist film by scraping off the planarizing film; forming the protective film on the upper part of the resist film; and removing the planarizing film that seals the openings in the resist film.
5. The method for forming a film according to claim 4, wherein the planarized film is an organic film.
6. A film formation method according to claim 1, comprising, in this order: impregnating the resist film with the metal at least into the upper part of the resist film; forming a conformal film along the step of the resist film on the upper surface of the resist film and the side surface of the opening; selectively etching the upper part of the conformal film to expose the upper part of the resist film; forming the protective film on the upper part of the resist film; and removing the conformal film remaining on the side surface of the opening.
7. The method for forming a film according to claim 6, wherein the conformal film is an inorganic film.
8. The method for forming a film according to claim 1, wherein the metal comprises one or more elements selected from Al, Ti, Zr, Zn, Hf, B, and In.
9. Processing container and The processing container includes a substrate holding section that holds the substrate inside, A gas supply unit that supplies gas to the inside of the processing container, A gas discharge unit that discharges gas from inside the processing container, A transport unit for loading and unloading the substrate into and out of the processing container, A control unit that controls the gas supply unit, the gas discharge unit, and the transport unit, and carries out the film formation method according to any one of claims 1 to 8, A film deposition apparatus equipped with the following features.